interface State {
  visitedViews: any[],
  cachedViews: any[],
}

interface Mutations<S = State> {
  ADD_VISITED_VIEW (state: S, view: {[key: string]: any}): void
  SET_CACHED_VIEW (state: S, view: {[key: string]: any}): void
  DEL_VISITED_VIEW (state: S, view: {[key: string]: any}): void
  DEL_CACHED_VIEW (state: S, view: {[key: string]: any}): void
  DEL_OTHERS_VISITED_VIEWS (state: S, view: {[key: string]: any}): void
  DEL_OTHERS_CACHED_VIEWS (state: S, view: {[key: string]: any}): void
  DEL_ALL_VISITED_VIEWS (state: S): void
  DEL_ALL_CACHED_VIEWS (state: S): void
  UPDATE_VISITED_VIEW (state: S, view: {[key: string]: any}): void
}

interface ActionContext {
  commit<K extends keyof Mutations>(
      key: K,
      payload ?: Parameters<Mutations[K]>[1],
  ): ReturnType<Mutations[K]>

  dispatch<K extends keyof Actions>(
      key: K,
      payload ?: Parameters<Actions[K]>[1],
  ): ReturnType<Actions[K]>
}



interface Actions {
  ACTION_ADDVIEW ({ dispatch }: ActionContext, view: {[key: string]: any}): void
  ACTION_ADD_VISITED_VIEW ({ commit }: ActionContext, view: {[key: string]: any}): void
  ACTION_ADD_CACHED_VIEW ({ commit }: ActionContext, view: {[key: string]: any}): void
  ACTION_DEL_VIEW ({ commit, dispatch }: ActionContext, view: {[key: string]: any}): Promise<unknown>
  ACTION_DEL_VISITED_VIEW ({ commit }: ActionContext, view: {[key: string]: any}): Promise<unknown>
  ACTION_DEL_CACHED_VIEW ({ commit }: ActionContext, view: {[key: string]: any}): Promise<unknown>
  ACTION_DEL_OTHERS_VIEW ({ commit, dispatch }: ActionContext, view: {[key: string]: any}): Promise<unknown>
  ACTION_DEL_OTHERS_VISITED_VIEW ({ commit }: ActionContext, view: {[key: string]: any}): Promise<unknown>
  ACTION_DEL_OTHERS_CACHED_VIEW ({ commit }: ActionContext, view: {[key: string]: any}): Promise<unknown>
  ACTION_DEL_ALL_VIEW ({ commit, dispatch }: ActionContext, view: {[key: string]: any}): Promise<unknown>
  ACTION_DEL_ALL_VISITED_VIEW ({ commit }: ActionContext, view: {[key: string]: any}): Promise<unknown>
  ACTION_DEL_ALL_CACHED_VIEW ({ commit }: ActionContext, view: {[key: string]: any}): Promise<unknown>
  ACTION_UPDATE_VISITED_VIEW ({ commit }: ActionContext, view: {[key: string]: any}): void
}

const state: State = {
  visitedViews: [],
  cachedViews: []
};

const mutations: Mutations = { 
	ADD_VISITED_VIEW: (state, view) => {
    if (state.visitedViews.some(v => v.path === view.path)) return
    if (view.meta && view.meta.noTagsView) return
    state.visitedViews.push(
      Object.assign({}, view, {
        title: view.meta.title || 'no-name'
      })
    )
	},
  SET_CACHED_VIEW: (state, view) => {
    if (state.cachedViews.includes(view.name)) return
    if (!view.meta.noCache) {
      state.cachedViews.push(view.name)
    }
  },
  DEL_VISITED_VIEW: (state, view) => {
    for (const [i, v] of state.visitedViews.entries()) {
      if (v.path === view.path) {
        state.visitedViews.splice(i, 1)
        break
      }
    }
  },
  DEL_CACHED_VIEW: (state, view) => {
    for (const i of state.cachedViews) {
      if (i === view.name) {
        const index = state.cachedViews.indexOf(i)
        state.cachedViews.splice(index, 1)
        break
      }
    }
  },
  DEL_OTHERS_VISITED_VIEWS: (state, view) => {
    state.visitedViews = state.visitedViews.filter(v => {
      return v.meta.affix || v.path === view.path
    })
  },
  DEL_OTHERS_CACHED_VIEWS: (state, view) => {
    for (const i of state.cachedViews) {
      if (i === view.name) {
        const index = state.cachedViews.indexOf(i)
        state.cachedViews = state.cachedViews.slice(index, index + 1)
        break
      }
    }
  },
  DEL_ALL_VISITED_VIEWS: state => {
    // keep affix tags
    const affixTags = state.visitedViews.filter(tag => tag.meta.affix)
    state.visitedViews = affixTags
  },
  DEL_ALL_CACHED_VIEWS: state => {
    state.cachedViews = []
  },
  UPDATE_VISITED_VIEW: (state, view) => {
    for (let v of state.visitedViews) {
      if (v.path === view.path) {
        v = Object.assign(v, view)
        break
      }
    }
  }

};

const actions: Actions = {
  ACTION_ADDVIEW({ dispatch }, view): void {
    dispatch('ACTION_ADD_VISITED_VIEW', view)
    dispatch('ACTION_ADD_CACHED_VIEW', view)
  },
  
  ACTION_ADD_VISITED_VIEW ({ commit }, view) {
		commit('ADD_VISITED_VIEW', view);
	},
  ACTION_ADD_CACHED_VIEW ({ commit }, view) {
    commit('SET_CACHED_VIEW', view)
  },

  ACTION_DEL_VIEW({ dispatch }, view) {
    return new Promise(resolve => {
      dispatch('ACTION_DEL_VISITED_VIEW', view)
      dispatch('ACTION_DEL_CACHED_VIEW', view)
      resolve({
        visitedViews: [...state.visitedViews],
        cachedViews: [...state.cachedViews]
      })
    })
  },
  
  ACTION_DEL_VISITED_VIEW({ commit }, view) {
    return new Promise(resolve => {
      commit('DEL_VISITED_VIEW', view)
      resolve([...state.visitedViews])
    })
  },
  ACTION_DEL_CACHED_VIEW({ commit }, view) {
    return new Promise(resolve => {
      commit('DEL_CACHED_VIEW', view)
      resolve([...state.cachedViews])
    })
  },

  ACTION_DEL_OTHERS_VIEW({ dispatch }, view) {
    return new Promise(resolve => {
      dispatch('ACTION_DEL_OTHERS_VISITED_VIEW', view)
      dispatch('ACTION_DEL_OTHERS_CACHED_VIEW', view)
      resolve({
        visitedViews: [...state.visitedViews],
        cachedViews: [...state.cachedViews]
      })
    })
  },

  ACTION_DEL_OTHERS_VISITED_VIEW({ commit }, view) {
    return new Promise(resolve => {
      commit('DEL_OTHERS_VISITED_VIEWS',view)
      resolve([...state.visitedViews])
    })
  },

  ACTION_DEL_OTHERS_CACHED_VIEW({ commit }, view) {
    return new Promise(resolve => {
      commit('DEL_OTHERS_CACHED_VIEWS', view)
      resolve([...state.cachedViews])
    })
  },

  ACTION_DEL_ALL_VIEW({ dispatch }, view) {
    return new Promise(resolve => {
      dispatch('ACTION_DEL_ALL_VISITED_VIEW', view)
      dispatch('ACTION_DEL_ALL_CACHED_VIEW', view)
      resolve({
        visitedViews: [...state.visitedViews],
        cachedViews: [...state.cachedViews]
      })
    })
  },

  ACTION_DEL_ALL_VISITED_VIEW({ commit }) {
    return new Promise(resolve => {
      commit('DEL_ALL_VISITED_VIEWS')
      resolve([...state.visitedViews])
    })
  },

  ACTION_DEL_ALL_CACHED_VIEW({ commit }) {
    return new Promise(resolve => {
      commit('DEL_ALL_CACHED_VIEWS')
      resolve([...state.cachedViews])
    })
  },

  ACTION_UPDATE_VISITED_VIEW({ commit }, view) {
    commit('UPDATE_VISITED_VIEW', view)
  },

};

export default {
	namespaced: true,
	state,
	mutations,
	actions
}